Adapter for fluid operated driving tool

ABSTRACT

An adapter for mounting on a fluid operated driving tool which prevents operation of the tool until a predetermined condition has been attained, the condition being that the workpiece being driven must encounter substantial resistance to penetration of the base material.

United States Patent [191 Hallock, Jr.

[451 Dec. 17,1974

[ ADAPTER FOR FLUID OPERATED DRIVING TOOL [76] Inventor: Robert L.Hallock, Jr., 48 Rockland Ave., Larchmont, NY. 10538 [22] Filed: Feb.25, 1974 21 Appl. No.: 445,766

[52] US. Cl 173/15, 173/131, 227/7, 227/1 13 [51] Int. Cl. B25c l/00,B250 3/00 [58] Field of Search 173/15,16, 17; 227/113, 227/6, 7, 8

[56] References Cited UNITED STATES PATENTS 2,632,890 3/1953 Tietig227/113 Langas 173/2 Smith 173/17 Primary Examiner-Ernest R. PurserAssistant Examiner-William F. Pate, lll Attorney, Agent, or Firm-A.Yates Dowell, Jr.

[ 5 7 ABSTRACT An adapter for mounting on a fluid operated driving toolwhich prevents operation of the tool until a predetermined condition hasbeen attained, the condition being that the workpiece being driven mustencounter substantial resistance to penetration of the base material.

7 Claims, 5 Drawing Figures ADAPTER FOR FLUID OPERATED DRIVING TOOLBACKGROUND OF THE INVENTION 1. Field of the Invention This inventionrelates generally to fluid operated driving tools and relatesparticularly to tools having safety devices for preventing operation ofthe driving tool until the fastener being driven is in a correctposition.

2. Description of the Prior Art Heretofore the attaching of coveringmaterial such as relatively soft insulation boards or shingles, sidingor the like to a foundation such as wood or sheet metal has been done bya carpenter holding a nail on the covering material and driving the nailwith a hammer. In order to speed up the operation and thereby reduce thetime and labor involved, fluid operated driving tools have been providedfor driving nails, staples and other penetrating fasteners when thetrigger of the tool is operated. Although driving tools have increasedproduction while reducing the manual labor involved, they have beenhazardous since an operator could intentionally or accidentally activatethe trigger in some position other than the driving position of a toolcausing a fastener to be expelled from the tool at substantial velocitywhich could cause personal injury to any workman the fastener mightstrike, or could cause damage to a structure which the fastener hits.

Some efforts have been made to improve the driving tools by placinganadapter on the driving end of the tool and connecting such adapter tothe trigger so that the adapter had to be placed in engagement with thematerial intowhich the fastener was to be driven and a downward forceapplied thereto before the trigger could be operated. An example of thistype of structure is the patent to Langas U.S. Pat. No. 3,194,324. Otherefforts, such as the patents to Hansen U.S. Pat. No. 1,846,804 and SmithU.S. Pat. No. 3,438,449, have been provided in which the fastener or theworkpiece being driven was adapted to engage the driving member of thegun to cock such member before the gun could be operated.

in the construction of industry, it is frequently desirable to attachrelatively easily penetrable insulation board to sheet metal siding,roofing and the like and in order to do this nails or other fastenerssuch as disclosed in the R. L. Hallock U.S. Pat. No. 2,967,448 have beenprovided which will penetrate and grip sheet metal to hold theinsulating material in position. Sheet metal siding and roofing deckshave included generally rectangular corrugations for extra strength sothat portions of the insulating board engaged the hills of thecorrugated sheet metal while a space occurred between the insulatingboard and the valleys of the corrugated sheet metal. Since theinsulating board has not been transparent, the nails were driven blindlyand the workman who used a power operated driving tool did not knowwhether the nail had penetrated the sheet metal or whether the nail wasdriven into a void so that it had no holding capacity.

SUMMARY OF THE INVENTION The present invention is an adapter for a fluidoperated driving tool which is used for blind driving a fastener'toattach relatively soft insulation board to a corrugated sheet metalsubstructure. The adapter prevents operation of the driving tool untilthe fastener is pushed through the insulation board and is aligned withone of the hills of the corrugated substructure so that a fastener,which is aligned with a void and does not engage the substructure,cannot be driven by the tool.

It is an object of the invention to provide a safety adapter for a fluidoperated driving tool which not only prevents inadvertent operation ofthe tool, but also prevents operation of the tool until such time as thefastener being driven is located in a position to penetrate thesubstructure.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation of a fluidoperated driving tool with the adapter attached thereto.

FIG. 2 is a bottom plan thereof.

FIG. 3 is an enlarged vertical section illustrating the initial step indriving the fastener.

FIG. 4 is a section similar to FIG. 3 illustrating the adapter in aposition such that the trigger of the tool can be energized for drivingthe fastener.

FIG. 5 is a section similar to FIG. 3 illustrating the fastener inalignment with a void in which position the tool is inoperative.

DESCRIPTION OF THE PREFERRED EMBODIMENT With continued reference to thedrawing, a fluid operated driving tool 10 is provided having a handle 11connected to one end of a pressure hose 12 the opposite end of which isconnected to a source of fluid under pressure (not shown). The handle 11includes a control valve 13 having a plunger (not shown) which controlsthe flow of air under pressure from the hose I2 to the conventionalpressure operated driving mechanism within the tool 10. The valve 13includes a stem 14 which extends outwardly of the handle 11 in aposition to be engaged by a portion ofa trigger 15 for operating thevalve. The trigger 15 includes a generally U-shaped housing 16 swingablyconnected by a pivot 17 to a pair of lugs 18 extending outwardly fromthe driving tool 10. The open side of the U-shaped housing 16 faces thehandle 11 substantially in alignment with the outer end of the stem 14.A trigger lever 19 is swingably mounted on a pivot 20 at the outer endof the U-shaped housing I6 while the inner end of such lever is freelymovable.

Normally movement of the trigger 15 toward the valve stem I4 will notactuate the valve since the trigger lever 19 is free to rotate. Beforethe movement of the trigger 15 can actuate the valve 13, a trigger arm21 must be moved upwardly to bear against the inner end of the lever 19so that when the trigger is moved the lever 19 is no longer free torotate andtherefore moves the stem 14 inwardly to actuate the valve 13.

In order to move the trigger arm upwardly, an

adapter 25 is mounted on the end of the driving tool 10 and such adapterincludes a body 26 which is fixed to the driving tool in any desiredmanner, as by screws or other fasteners 27. The inner portion 28 of thebody 26 is of a configuration corresponding generally to theconfiguration of the end of the driving tool I0 and is connected by areduced neck 29 to a generally cylindrical externally threaded outerportion 30. The body 26 has a bore 31 extending generally along thevertical axis which communicates with a concentric counterbore 32extending inwardly from the inner portion 28,

and a concentric counterbore 33 extending inwardly from the outerportion 30. A guide bearing 34 is mounted within the bore 31 for guidingthe driving member 35 of the driving tool 10.

A head or cap 38 threadedly engages the'o uter portion 30 of the body 26and such head includes a relatively large axial bore 39 connected by ashoulder 40 to a concentric counterbore 41 adjacent to the body 26. Agenerally cylindrical holder 42 has an upper portion 43 slidablyreceived within the counterbore 41 of the head and a reduced lowerportion 44 slidably received within the bore 39. The upper portion 43 ofthe holder normally rests on the shoulder 40 of the head, as illustratedin FIGS. 3 and 5.

The holder 42 has a bore 45 along the vertical axis which is slightlylarger than the diameter of the driving member 35 and such bore isconnected by a shoulder 46 to a concentric counterbore 47. Thecounterbore 47 extends most of the way through the holder 42 and isadapted to receive a cylindrical magnet 48 which rests against theshoulder 46. The magnet 48 is provided with a central opening 49substantially in alignment with and of a size corresponding to the bore45 of the holder so that the driving member 35 can pass through themagnet. Preferably a shim or flat washer 50 is mounted on the uppersurface of the magnet 48.

A relatively strong spring or other resilient member 51 surrounds thelower end of the driving member 35 and has its lower end disposed withinthe counterbore 47 of the holder 42 and bearing against the shim 50,while the upper end of such spring is received within the counterbore 33of the body 26. The spring 51 normally maintains the holder 42 in spacedrelationship with the body 26.

An upwardly extending post 52 is fixed to the holder 42 and such post isslidably mounted in an opening 53 in the outer portion 30 of the body26. The post 52 is provided with a reduced upper end 54 which extendsinto the opening between the upper and lower portions of the body andadjacent to the neck 29 thereof. The inner portion 28 of the body 26 hasan upwardly extending cylindrical recess 55 in alignment with the post52 and such recess is adapted to receive a spring or other resilientmember 56. The lower end of the trigger arm 21 is provided with anangularly disposed inwardly extending flange 57 the inner end of whichis provided with an opening which receives the reduced end 54 of thepost and is held in position by the spring 56. If desired the lowerportion of the arm 21 may have a guide slot 58 in which a guide pin 59is slidably received and such pin is connected to the inner portion 28of the body 26.

In the operation of the device, when an insulation board 60 is to bemounted on a corrugated substructure 61, it is desirable to drive aroofing nail or other fastener 62 through the hills only of thesubstructure to make certain that the insulation is firmly connected tothe substructure. In order to do this, the head of the nail 62 is placedin engagement with the lower end of the holder 42 where it is attractedby themagnet 48 and held in position. The driving tool then is movedtoward the insulation 60 and a downward force is applied thereto tocause the stem of the nail to penetrate the relatively soft insulationwithout substantially compressing the spring 51. 1f the penetratingpoint of the nail engages one of the hills of the substructure 61, asillustrated in FIG. 3, further downward movement of the driving toolovercomes the tension of the spring 51 so that the holder 42 movesupwardly from the outer stop or shoulder 40 into engagement with theouter portion 30 of the body 26 which provides an inner stop. Upwardmovement of the holder causes the post 52 to move upwardly and move thearm 21 upwardly so that the upper end of the arm abuts the free end ofthe trigger lever 19 so that when the trigger 15 is depressed the stem14 of the valve 13 is moved and the valve is actuated so that air underpressure causes the driving member 35 to be extended to drive the nail62 through the substructure 61, as illustrated in phantom in FIG. 4. Assoon as the nail is driven, the spring 51 returns the holder 42 to itslower position and deactivates the valve 13.

With particular reference to FIG. 5, if the nail 62 should be alignedwith one of the valleys of the substructure when the nail is pushedthrough the insulation, the lower end of the head 38 engages the uppersurface of the insulation before the nail encounters sufficientresistance to move the holder 42 and therefore the trigger 15 is stillinoperative. When this condition occurs, the driving tool is raisedafter which the nail is pulled from the insulation and is again placedagainst the lower end of the holder 42 and the process is repeated untilthe nail engages one of the hills of the substructure. After two spacednails have been driven through the same hill of the substructure, a linemay be drawn between the two nails to assist the workman in locating ahill into which the nail may be driven.

I claim:

1. Apparatus for use with a tool having a power driven member fordriving a fastener into a media which provides a predeterminedresistance to the penetration of the fastener, said apparatus comprisingholder means mounted for reciprocation coaxially of the power drivenmember and having a fastener engaging portion which is normally spacedoutwardly of said power driven member, said holder means beingconstructed and arranged to permit said power driven member to contactthe fastener without obstruction from said holder means, spaced innerand outer stop means limiting the movement of said holdermeans,resilient means normally urging said holder means toward said outer stopmeans, said holder means being movable toward said inner stop means uponengagement of the fastener with media of predetermined resistance priorto operation of said driving member, said resilient means not permittingmovement of said holder means in media of less than saidpredeterminedresistance, and linkage engaged by said holder means andconditioning said tool in non-driving state unless said holder means hasmoved to said inner stop means, whereby said fastener may beblind-nailed through an overlying media of less than said predeterminedresistance into an underlying media having areas of greater and areas ofless than said predetermined resistance and said power driven memberwill operate only when the fastener engages underlying media which isgreater than said predetermined resistance.

2. Apparatus for use with a tool having a power driven member fordriving a fastener into a media which provides a predeterminedresistance to the penetration of the fastener, said apparatus comprisinga body, means for mounting said body on said tool, a head carried bysaid body. holder means movably mounted within said head, resilientmeans normally urging said holder means away from said body under apredetermined force, said holder means adapted to removably support afastener having a stem extending v outwardly of said head, and safetymeans actuated by said holder means to prevent operation of said tooluntil the fastener engages a media which provides sufficient resistanceto overcome the force of said resilient means.

3. The structure of claim 2 in which said holder means includes an axialopening of a size to permit passage of the power driven member of thetool therethrough into engagement with the fastener.

4. The structure of claim 2 in which said holder means includes a magnetwhich releasably holds the fastener.

5. The structure of claim 2 in which said safety means includes a postfixed to said holder means and slidably mounted in said body, andlinkage connected to said post and conditioning the operating mechanismof the tool to inoperative position until said holder means has overcomethe force of said resilient means.

6. The structure of claim 2 including stop means spaced a predetermineddistance apart to limit movement of said holder means.

7. Apparatus for use with a tool, having a power driven member for blinddriving a fastener into a relatively high density media and which isoverlaid by a relatively low density media, said apparatus comprising abody, a head carried by said body, holding means movably mounted on saidhead, said holding means adapted to removably support a fastener havingthe stem extending outwardly of said head,'resilient means normallypositioning said holding means awayfrom the body with a force greaterthan the force required for the fastener to penetrate the low densitymedia, said holding means being movable toward said body upon engagementof the fastener with the relatively high density media but not uponengagement of the fastener with said relatively low density media, andsafety means actuated by said holding means to prevent operation of saidtool until the fastener engages the relatively high density media andsaid holding means is moved toward the body with a force sufficient toovercome said resil-

1. Apparatus for use with a tool having a power driven member fordriving a fastener into a media which provides a predeterminedresistance to the penetration of the fastener, said apparatus comprisingholder means mounted for reciprocation coaxially of the power drivenmember and having a fastener engaging portion which is normally spacedoutwardly of said power driven member, said holder means beingconstructed and arranged to permit said power driven member to contactthe fastener without obstruction from said holder means, spaced innerand outer stop means limiting the movement of said holder means,resilient means normally urging said holder means toward said outer stopmeans, said holder means being movable toward said inner stop means uponengagement of the fastener with media of predetermined resistance priorto operation of said driving member, said resilient means not permittingmovement of said holder means in media of less than said predeterminedresistance, and linkage engaged by said holder means and conditioningsaid tool in non-driving state unless said holder means has moved tosaid inner stop means, whereby said fastener may be blind-nailed throughan overlying media of less than said predetermined resistance into anunderlying media having areas of greater and areas of less than saidpredetermined resistance and said power driven member will operate onlywhen the fastener engages underlying media which is greater than saidpredetermined resistance.
 2. Apparatus for use with a tool having apower driven member for driving a fastener into a media which provides apredetermined resistance to the penetration of the fastener, saidapparatus comprising a body, means for mounting said body on said tool,a head carried by said body, holder means movably mounted within saidhead, resilient means normally urging said holder means away from saidbody under a predetermined force, said holder means adapted to removablysupport a fastener having a stem extending outwardly of said head, andsafety means actuated by said holder means to prevent operation of saidtool until the fastener engages a media which provides sufficientresistance to overcome the force of said resilient means.
 3. Thestructure of claim 2 in which said holder means includes an axialopening of a size to permit passage of the power driven member of thetool therethrough into engagement with the fastener.
 4. The structure ofclaim 2 in which said holder means includes a magnet which releasablyholds the fastener.
 5. The structure of claim 2 in which said safetymeans includes a post fixed to said holder means and slidably mounted insaid body, and linkage connected to said post and conditioning theoperating mechanism of the tool to inoperative position until saidholder means has overcome the force of said resilient means.
 6. Thestructure of claim 2 including stop means spaced a predetermineddistance apart to limit movement of said holder means.
 7. Apparatus foruse with a tool having a power driven member for blind driving afastener into a relatively high density media and which is overlaid by arelatively low density media, said apparatus comprising a body, a headcarried by said body, holding means movably mounted on said head, saidholding means adapted to removably support a fastener having the stemextending outwardly of said head, resilient means normally positioningsaid holding means away from the body with a force greater than theforce required for the fastener to penetrate the low density media, saidholding means being movable toward said body upon engagement of Thefastener with the relatively high density media but not upon engagementof the fastener with said relatively low density media, and safety meansactuated by said holding means to prevent operation of said tool untilthe fastener engages the relatively high density media and said holdingmeans is moved toward the body with a force sufficient to overcome saidresilient means.